Electrochemical device for producing hydrogen

ABSTRACT

The present invention provides an electrolytic device and apparatus comprising the same, where the electrolytic device includes a means for generating a first gas stream that is enriched with a first gas. In particular, the electrolytic device of the invention comprises a first tubular electrode and a second tubular electrode that is coaxially located within the first tubular electrode. The second tubular electrode comprises a plurality of orifices that is adapted to producing a first gas stream that is enriched with a first gas.

FIELD OF THE INVENTION

The present invention relates to an electrolytic device and apparatus comprising the same, where the electrolytic device comprises a first tubular electrode and a second tubular electrode that is coaxially located within the first tubular electrode. The second tubular electrode comprises a plurality of orifices that is adapted to producing a first gas stream that is enriched with a first gas.

BACKGROUND OF THE INVENTION

Electrolysis has been utilized in many forms for producing gases from a liquid solution. Most electrolysis methods use a flat plate system. All electrolytic devices produce both oxygen and hydrogen gases from an aqueous electrolyte solution in substantially a theoretical mixture amount, i.e., 66⅔% hydrogen and 33⅓% oxygen. If a concentrated oxygen or hydrogen gas is desired, it must be separated from one another. While a wide variety of methods are known to one skilled in the art for separating gases, typically separation of gases in electrolytic devices is achieved using a gas permeable membrane. Gas permeable membranes allow one type of gas (e.g., hydrogen) to pass through the membrane while preventing the other gas (e.g., oxygen) from passing through. These gas permeable membranes typically achieve separation of gases based on the molecular size of gases.

Use of a gas permeable membrane adds to the complexity of the electrolytic devices as well as the overall cost of the electrolytic devices. For example, certain gas permeable membranes may not be compatible with a strongly basic or acidic electrolyte solution, thereby requiring a particular electrolyte solution to be used within the electrolyte device. Currently, no electrolytic device is known that can separate gases without the use of a gas permeable membrane or some other mechanical means.

Therefore, there is a need for an electrolytic device that can produce hydrogen enriched gas from an aqueous solution without a need for a gas permeable membrane or other gas separation processes.

SUMMARY OF THE INVENTION

The present inventors have discovered that by providing a plurality of orifices within a certain electrode in a tube-in-tube electrolytic device affords separation of gases without a need for a gas permeable membrane or other gas separation means currently utilized in conventional electrolytic gas production devices and methods.

Accordingly, some aspects of the invention provide an electrochemical device adapted for producing a gas stream enriched with a first gas using electrolytic decomposition of a fluid. In some embodiments, devices of the invention include:

-   -   a first tubular electrode; and     -   a second tubular electrode located within the interior space of         said first tubular electrode,         wherein     -   one of said first or said second tubular electrode is configured         as a cathode and the other is configured as an anode;     -   the inner cross-sectional area of said first tubular electrode         is greater than the outer cross-sectional area of said second         tubular electrode; and     -   said second tubular electrode comprises a plurality of orifices         along its length, wherein said plurality of orifices is adapted         for producing a first gas stream that is enriched with a first         gas within the inner space or the external space of said second         tubular electrode.

In some embodiments, said plurality of orifices is adapted to produce the first gas stream that is enriched with said first gas within the inner space or exterior of said second tubular electrode.

Yet in other embodiments, said plurality of orifices is adapted to produce said first gas stream within the inner space of said second tubular electrode.

Still in other embodiments, said device is adapted to produce said first gas stream within the exterior space of said second tubular electrode.

In other embodiments, the electrochemical device further comprises a first gas outlet adapted to allow said first gas stream to be obtained through said first gas outlet. Within these embodiments, in some instances said first gas outlet is operative connected to the inner space of said second tubular electrode. Still in other instances, said first gas outlet is operative connected to the external space of said second tubular electrode.

Still yet in other embodiments, said electrochemical device is further adapted to produce a second gas stream that is enriched with a second gas from the fluid.

Yet still in other embodiments, said electrochemical device further comprises a second gas outlet that is adapted to allow said second gas stream to be obtained through said second gas outlet. Within these embodiments, in some instances said device is adapted to produce said first or said second gas stream within the inner space of said second tubular electrode and to produce the other gas stream within the exterior space of said second tubular electrode.

Another aspect of the invention provides an electrochemical device for producing hydrogen from an aqueous electrolyte solution, said device comprising:

-   -   a first tubular electrode; and     -   a second tubular electrode located within the interior space of         said first tubular electrode and arranged coaxially relative to         said first tubular electrode,         wherein     -   one of said first or said second tubular electrode is configured         as a cathode and the other is configured as an anode;     -   the inner cross-sectional area of said first tubular electrode         is greater than the outer cross-sectional area of said second         tubular electrode; and     -   said second tubular electrode comprises a plurality of orifices         along its length, wherein said plurality of orifices is adapted         for producing a hydrogen enriched gas stream within the inner         space or the external space of said second tubular electrode.

In some embodiments, said plurality of orifices is adapted to produce a hydrogen gas enriched stream within the inner space of said second tubular electrode. In some instances, said hydrogen enriched gas stream comprises at least 75% hydrogen.

Still in other embodiments, said device is further adapted to produce oxygen enriched gas stream within the exterior surface of said second tubular electrode.

In other embodiments, said device is adapted to produce said hydrogen enriched gas stream within the exterior space of said second tubular electrode.

Yet in other embodiments, the electrochemical device further comprises a gas outlet operatively connected to hydrogen enriched gas stream, wherein said gas outlet is adapted to allow hydrogen enriched gas stream to be obtained through said gas outlet.

In some embodiments, said second tubular electrode is a cathode.

Still in other embodiments, the electrochemical device further comprises an electrolytic aqueous solution having a pH of about 11 or less. In some instances, said electrolytic aqueous solution comprises about 7% or less of KOH by wt.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a schematic illustration of one particular embodiment of an electrolytic device of the present invention;

FIG. 1B is a top-view schematic illustration of one particular embodiment of an electrolytic device of the present invention;

FIG. 2 is another embodiment of a second electrode of the invention having a plurality of orifices that are oval-shaped;

FIG. 3 is a schematic illustration of an electrolytic device of the invention within an electrolytic cell;

FIG. 4 is one particular dimension of a second electrode of the present invention;

FIG. 5 shows two embodiments of a first electrode of the present invention with different inner diameters; and

FIG. 6 is a schematic illustration of one embodiment of an electrochemical device of the invention illustrating collection of hydrogen enriched gas stream from one outlet and collection of oxygen enriched gas stream from another outlet.

DETAILED DESCRIPTION OF THE INVENTION

The present invention will be described with regard to the accompanying drawings which assist in illustrating various features of the invention. In this regard, the present invention generally relates to an electrochemical (i.e., electrolytic) device for producing a gas from a fluid. In particular, the invention relates to an electrolytic device adapted for producing a gas stream enriched with a first gas from electrolytic decomposition of a fluid. As used herein, the term “enriched” means more than the theoretical mixture amount. For example, production of hydrogen and oxygen using an aqueous solution theoretically produces a gas mixture that is 66⅔% hydrogen and 33⅓% oxygen gas. However, devices of the invention produce a gas stream that is adapted to producing a gas stream with a gas mixture that is more than 66⅔% hydrogen. Typically, for production of hydrogen and oxygen using an aqueous solution, devices of the invention are adapted to producing a gas stream that is at least 70%, often at least 75%, more often at least 80%, still more often at least 85%, and most often at least 90% hydrogen. Conversely, the second gas stream will be enriched with oxygen.

One particular embodiment of electrolytic devices of the invention is generally illustrated in FIGS. 1-5. It should be appreciated that these drawings are merely provided for the purpose of illustrating the practice of the present invention and do not constitute any limitations on the scope thereof.

As can be seen in FIGS. 1A and 1B, an electrolytic device of the invention comprises a first tubular electrode 100 and a second tubular electrode 200 that is located within the interior space or the cavity of said first electrode 100. As used herein, the term “tubular” refers to having an inner cavity or a hollow interior space 300. The cross-section of the first and the second electrodes 100 and 200, respectively, can be any shape as long as there is not physical contact between the two electrodes within the cavity 300. Thus, while FIG. 1B shows both the first and the second electrodes 100 and 200, respectively, having a circular shape, the shape of the first and the second electrode cross-section area can independently be hexagonal, octagonal, rectangular, oval, elliptical, trapezoidal, square, triangular, etc., as long as no physical contact exists between the first and the second electrodes. First and second electrodes 100 and 200, respectively, include a corresponding electric connector 110 and 210, respectively, for connection to a suitable power source.

Referring again to FIGS. 1A, 1B and 3, the first and the second electrodes are typically arranged coaxially relative to one another, i.e., first electrode 100 and second electrode 200 has a concentric axis. First electrode 100 has an outer diameter 104A and an inner diameter 104B. Similarly, second electrode 200 has an outer diameter 204A and an inner diameter 204B. As can be seen in FIG. 1B, inner diameter 104B of first electrode 100 is greater than outer diameter 204A of second electrode 200. In this manner, the inner cross-sectional area of first electrode 100 is greater than the outer cross-sectional area of second electrode 200 throughout the length of first and second electrodes 100 and 200, respectively.

Referring to FIGS. 1A-B, 2 and 3, second electrode 200 also includes a plurality of orifices 208. The shape of the orifice can be any geometric shape such as circular, oval, elliptical, rectangular, etc. One of the key features of electrolytic devices of the invention is that the plurality of orifices 208 is adapted for producing a first gas stream that is enriched with a first gas within the inner space or the external space of said second electrode 200. For example, using an aqueous electrolyte solution, electrolytic devices of the invention are adapted to producing hydrogen enriched gas stream within the cavity or the inner space of second electrode 200 by having second electrode configured as a cathode and first electrode 100 configured as an anode. If the cathode and the anode is reversed, oxygen enriched gas stream is produced within the inner space of second electrode 200.

FIG. 3 shows electrolytic device of FIG. 1 within an electrolytic cell with a partially filled electrolytic solution 400. Thus, FIG. 3 shows one particular embodiment of an electrochemical device that utilizes the electrolytic device of the invention. As used herein, the term “electrolytic device” refers to any device having a cathode and an anode (i.e., first and the second electrodes 100 and 200) as described herein. The terms “electrolytic cell” and “electrochemical device” refer to an apparatus or a system that includes the electrolytic device of the invention and a solution that is used to produce a desired gas using the electrolytic device. As can be seen in FIG. 3, electrochemical device of the invention can include a first gas outlet 112 and a second gas outlet 212. These gas outlets are adapted to allow different gas streams (each of which is enriched with a different gas) to be obtained separately. In one particular embodiment, the second gas outlet 212 is adapted to allowing collection of a hydrogen enriched gas stream by using an aqueous electrolyte solution. The second gas outlet 212 is operative connected to the inner space 300 of said second electrode 200 such that any gas stream that is produced within inner space of second electrode 200 flows out of the electrochemical device through the outlet 212.

In some instances, as shown in FIG. 5, the first electrode 100 includes liquid inlet orifices 116A and 116B. This allows electrolyte solution to flow into the inner space between the first and the second electrodes 100 and 200, respectively, i.e., inner space 300 in FIG. 1B. It should be appreciated that the first and the second electrodes 100 and 200, respectively, are separated from one another to allow electrolytes solution to flow through the gap or the inner space between the first and the second electrodes. Any suitable methods and devices can be used in order to maintain this gap between the first and the second electrodes. For example, the second electrode 200 can be threaded such that a non-electric conducting screw (e.g., plastic, silicone, rubber, or any other material known to one skilled in the art) can be threaded onto the top, bottom, or both of the second electrode 200. The non-electric conducting screw (not shown) can be configured such that at least a portion of the non-electric conducting screw is inserted between the first and the second electrodes 100 and 200, respectively, i.e., inner space 300 between the first and the second electrodes. Alternatively, one can simply place one or more non-electric conducting materials between the first and the second electrodes while allowing electrolyte solution to flow through the inner space 300.

FIG. 6 is schematic illustration showing collection of different gas streams from electrochemical device of the invention. As can be seen in FIG. 6, the enclosed electrochemical device includes two different gas outlets 112 and 212. In particular, the electrolytic device shown in FIG. 6 is configured such that an oxygen enriched gas stream (indicated by vertical arrows) is produced between first electrode 100 (positive polarity, i.e., anode) and second electrode 200 (negative polarity, i.e., cathode). Oxygen enriched gas stream then exits space between first electrode 100 and second electrode 200 (indicated by curved arrow on top of first electrode 100) and is collected through first gas outlet 112. Hydrogen that is produced enters inner space of second electrode 200 through the plurality of orifices 208 (as indicated by diagonal arrows) and is collected through second gas outlet 212. In this manner, gas streams having differently enriched gas can be collected separately.

It should be appreciated that while the electrolytic device of the invention are primarily described as being useful in producing hydrogen gas from an aqueous electrolyte solution, the scope of the invention is not limited to hydrogen gas production. In fact, one skilled in the art having read the present disclosure can readily recognize a numerous applications for which the electrolytic device of the invention can be used. For example, applications for the electrolytic device of the invention include, but are not limited to, producing hydrogen, producing oxygen, producing various other gases and suitable by-product production, electrolysis of other solvents including non-aqueous electrolytic solvents, energy convertor in a fuel cells, capacitors, super capacitors, redox battery, etc.

In some embodiments, the electrolytic device of the invention is a single stage unit. It should also be appreciated that the electrolytic device of the invention can be utilized in any suitable apparatus, in multiple configurations, e.g., in series or parallel or a combination thereof. Such multiple configurations allow for high levels of hydrogen gas to be produced at low power levels.

As can be seen in the accompanying draws, in some embodiments the length of first electrode 100 is smaller than the second electrode 200. As discussed above, the first electrode 100 can be configured as an anode or cathode as long as the second electrode 200 is configured to be a complementary electrode, i.e., when first electrode 100 is cathode, second electrode 200 is anode and when first electrode 100 is anode then second electrode 200 is cathode.

Second electrode 200 has a plurality of orifices that is adapted to allow enrichment of one gas within the inner space of second electrode 200. The presence of gas separating orifices in second electrode 200 eliminates or reduces the need for a separate gas separation means such as a gas separation membrane, etc.

Two or more electrolytic devices of the invention can be used in parallel, series, and any multiple variations thereof. Moreover, one skilled in the art having read the present disclosure can readily recognize various modifications to the designs that can be incorporated to the electrolytic device of the invention. For example, following are some of the changes that can be incorporated to the electrolytic device of the invention: sizes and shapes of tubes; singular and multiple tubular electrodes; different materials for electrodes (e.g., metals, such as iron, copper, zinc, and precious metals such as platinum, gold, silver, as well as metal alloys such as stainless, brass, etc., ceramics, and any other electric conducting material including combination of materials); size and shape of orifices in the second electrode (e.g., holes, slots, and any other cut configurations); electrode configurations; electrode positions (such as distance between the first and the second electrodes); horizontal, vertical or any other angular position of electrodes; placement of filters (or gas permeable or charge transfer membranes), PEM's, and suchlike devices; coating materials for electrodes (e.g., special coating materials, nano, micro, and other electrode coatings); special designs relating to the surfaces of the electrodes (e.g., to increase the surface area); using a tube-like electrodes (e.g., coil or helically shaped electrodes).

It should be appreciated that the voltage, current, frequency, polarity shifting, pulsing and other variation of applying the necessary electricity can be used with electrolytic device of the invention. Typically, one skilled in the art can readily determine a suitable voltage, current, frequency, and other electricity variables for a particular use. Some of the variables, of course will depend on a variety of factors such as the size of the electrodes, the electrolytic solution used, the amount or the rate of hydrogen gas production desired, etc.

One particular use of electrolytic device of the invention will now be described in reference to producing hydrogen from an aqueous electrolytic solution. However, as described above, the utility of the electrolytic device of the invention is not limited to producing hydrogen.

The global demand for energy has steadily been increasing. With finite availability of fossil fuel, and more significantly, damaging effects of fossil fuel on the environment, there is a great demand for developing sustainable, non-fossil based, “green” energy sources for large scale use. Hydrogen gas has been one of the most promising candidates for clean, renewable energy source. There are a wide variety of methods for producing hydrogen, including electrolysis of water. While a number of electrodes and electrolyte materials have been developed and are currently under investigation for electrolysis of water to produce hydrogen, currently no commercially viable electrode design is available for large scale use.

Furthermore, many conventional large scale production of hydrogen by electrolysis use a strongly alkaline solution. Unfortunately, majority of conventional electrolysis to produce hydrogen also requires high powered, high pressure, heavy, oversized apparatus that tend to need heating, cooling, fanning, purging or filtering tools. In other conventional hydrogen production methods through efficient electrolysis involve the use of various strongly corrosive or toxic electrolytes, e.g., KOH, which require proper handling and safety measures. Generally, in conventional large scale use of the electrolysis apparatus, cell leakage and environmental exposure is always a possibility creating risks both to human and environment.

While electrolytic device of the invention can be used with any conventional electrolytic solution known to one skilled in the art as well as any other electrolytic solution that may be developed, in one particular embodiment, the electrolytic device of the invention uses electrolytic solution that is safer than conventional commercial electrolytes. In some instances, the electrolyte solution used with electrolytic device of the invention is non-toxic. In some instances, electrolytic solution used in conjunction with the electrolytic device of the invention contains FDA approved and generally recognized as safe in the levels contained in the electrolytic solution. Moreover, some components of electrolyte solution used are fully biodegradable. Still in other instances, components of electrolyte solution that is used with the electrolytic device of the invention occur in nature and are used at concentrations no higher than what would be found naturally in the environment.

In electrolysis, water is decomposed to hydrogen and oxygen, by passing a current through electrodes in the presence of suitable substances, called electrolytes. Electric current causes positively charged hydrogen ions to migrate to the negatively charged cathode, where a reduction takes place in order to form hydrogen atoms. The atoms formed then combine to form gaseous hydrogen molecules (H₂). On the other hand, oxygen is formed at the other electrode (the positively charged anode). The stoichiometry of the reaction is two volumes of hydrogen to one volume of oxygen. One of the important considerations in the construction of electrolysis units is to use adequate electrodes to avoid unwanted reactions, which can produce impurities in the hydrogen gas. Conventional electrolytic cells also use a separating membrane that allows the passage of ions or electrons and not oxygen or hydrogen atoms. As discussed herein, electrolytic device of the invention eliminates or reduces the need for such a separating membrane.

In one particular embodiment, the electrolyte solution used in conjunction with the electrolytic device of the invention include 7% or less of KOH by weight. It should be noted conventional electrolyte solution using KOH has at least 10% or more of KOH, typically about 30% KOH by weight. Such a strongly basic electrolytic solution is caustic, and poses a significant danger to human and environment. In contrast, by using heretofore unheard of low concentration of KOH in electrolyte solution significantly reduces, in fact substantially eliminates, the danger to human and environment due to a possible leakage of electrolyte solution.

In some embodiments, the pH of the electrolyte solution used in conjunction with the electrolytic device of the invention is about pH 11 or less, typically pH 10 or less.

The electrolyte solution of the invention can also include one or more of the following components, all of which are present in concentrations that does not pose danger to human or environment: ascorbic acid; phosphoric acid; citric acid; acetic acid; sorbitol; potassium carbonate; propionic acid; sodium propionate; sucrose; lithium carbonate; lithium citrate; magnesium chloride; sodium teraborate; sodium acetate; and sodium sulphate. Other suitable electrolyte solution is disclosed in a commonly assigned patent application that is filed even date herewith.

In one particular embodiment, the electrolyte solution is prepared by adding 25 g of lithium citrate to 1 L of water. Catalytic promoters can also be added to the electrolyte at this point such as, but is not limited to, at least one component from the list of components provided above or any mixture thereof.

Additional objects, advantages, and novel features of this invention will become apparent to those skilled in the art upon examination of the following examples thereof, which are not intended to be limiting. In the Examples, procedures that are constructively reduced to practice are described in the present tense, and procedures that have been carried out in the laboratory are set forth in the past tense.

Examples

A device similar to that shown in FIG. 6 was powered by a direct current (DC) supply at a suitable level to produce hydrogen and oxygen, e.g., 8 volts and 8 amps, using various electrolyte solutions. First electrode 100 was positively charged (i.e., anode) and second electrode 200 was negatively charged (i.e., cathode.) The testing was done over a 2 hour period. The gas produced through first gas outlet 112 and second gas outlet 212 were collected and analyzed using a gas chromatography. In addition to hydrogen and oxygen gases, a very small amount of moisture (i.e., water vapor), carbon monoxide, carbon dioxide and methane gases were also produced depending on the composition of the electrolyte solution. In general, at least 95% of the total gases were hydrogen and oxygen. The amount of hydrogen and oxygen gases produced through second gas out let 212 and first gas outlet 112, respectively, were analyzed and the results are shown below.

Analysis of Gases from Second as Outlet 212

% H₂ % O₂ H₂:O₂ Ratio Moisture (%) 80.4 16.1 5.0:1.0 3.5 89.9 6.6 13.6:1.0  3.5 Analysis of Gases from First Gas Outlet 112

% O₂ % H₂ O₂:H₂ Ratio Moisture (%) 88.9 7.5 11.8:1.0 3.6 91.4 5.0 18.3:1.0 3.6 As the above results show, electrochemical device of the invention separated hydrogen gas from oxygen gas without a need for a gas permeable membrane or any other gas separation means at a significant hydrogen purity level. The theoretical ratio of H₂ to O₂ produced in electrolysis of water is 2:1 (i.e., two parts hydrogen gas per one part oxygen gas). However, as can be seen above, electrochemical device of the invention produces a significantly higher ratio of hydrogen gas in the gas outlet 212.

The foregoing discussion of the invention has been presented for purposes of illustration and description. The foregoing is not intended to limit the invention to the form or forms disclosed herein. Although the description of the invention has included description of one or more embodiments and certain variations and modifications, other variations and modifications are within the scope of the invention, e.g., as may be within the skill and knowledge of those in the art, after understanding the present disclosure. It is intended to obtain rights which include alternative embodiments to the extent permitted, including alternate, interchangeable and/or equivalent structures, functions, ranges or steps to those claimed, whether or not such alternate, interchangeable and/or equivalent structures, functions, ranges or steps are disclosed herein, and without intending to publicly dedicate any patentable subject matter. 

1. An electrochemical device adapted for producing gas through electrolytic decomposition of a fluid, said device comprising: a first tubular electrode; and a second tubular electrode located within the interior space of said first tubular electrode and arranged coaxially relative to said first tubular electrode, wherein one of said first or said second tubular electrode is configured as a cathode and the other is configured as an anode; the inner cross-sectional area of said first tubular electrode is greater than the outer cross-sectional area of said second tubular electrode; and said second tubular electrode comprises a plurality of orifices along its length, wherein said plurality of orifices is adapted for producing a first gas stream that is enriched with a first gas within the inner space or the external space of said second tubular electrode.
 2. The electrochemical device of claim 1, wherein said plurality of orifices is adapted to produce the first gas stream that is enriched with said first gas within the inner space or exterior of said second tubular electrode.
 3. The electrochemical device of claim 1, wherein said plurality of orifices is adapted to produce said first gas stream within the inner space of said second tubular electrode.
 4. The electrochemical device of claim 1, wherein said device is adapted to produce said first gas stream within the exterior space of said second tubular electrode.
 5. The electrochemical device of claim 1 further comprising a first gas outlet adapted to allow said first gas stream to be obtained through said first gas outlet.
 6. The electrochemical device of claim 5, wherein said first gas outlet is operative connected to the inner space of said second tubular electrode.
 7. The electrochemical device of claim 5, wherein said first gas outlet is operative connected to the external space of said second tubular electrode.
 8. The electrochemical device of claim 1, wherein said electrochemical device is further adapted to produce a second gas stream that is enriched with a second gas from the fluid.
 9. The electrochemical device of claim 8, wherein said electrochemical device further comprises a second gas outlet that is adapted to allow said second gas stream to be obtained through said second gas outlet.
 10. The electrochemical device of claim 9, wherein said device is adapted to produce said first or said second gas stream within the inner space of said second tubular electrode and to produce the other gas stream within the exterior space of said second tubular electrode.
 11. An electrochemical device for producing hydrogen from an aqueous electrolyte solution, said device comprising: a first tubular electrode; and a second tubular electrode located within the interior space of said first tubular electrode and arranged coaxially relative to said first tubular electrode, wherein one of said first or said second tubular electrode is configured as a cathode and the other is configured as an anode; the inner cross-sectional area of said first tubular electrode is greater than the outer cross-sectional area of said second tubular electrode; and said second tubular electrode comprises a plurality of orifices along its length, wherein said plurality of orifices is adapted for producing a hydrogen enriched gas stream within the inner space or the external space of said second tubular electrode.
 12. The electrochemical device of claim 11, wherein said plurality of orifices is adapted to produce a hydrogen gas enriched stream within the inner space of said second tubular electrode.
 13. The electrochemical device of claim 12, wherein said hydrogen enriched gas stream comprises at least 75% hydrogen.
 14. The electrochemical device of claim 12, wherein said device is further adapted to produce oxygen enriched gas stream within the exterior surface of said second tubular electrode.
 15. The electrochemical device of claim 11, wherein said device is adapted to produce said hydrogen enriched gas stream within the exterior space of said second tubular electrode.
 16. The electrochemical device of claim 11 further comprising a gas outlet operatively connected to hydrogen enriched gas stream, wherein said gas outlet is adapted to allow hydrogen enriched gas stream to be obtained through said gas outlet.
 17. The electrochemical device of claim 11, wherein said second tubular electrode is a cathode.
 18. The electrochemical device of claim 11 further comprising an electrolytic aqueous solution having a pH of about 11 or less.
 19. The electrochemical device of claim 18, wherein said electrolytic aqueous solution comprises about 7% or less of KOH.
 20. The electrochemical device of claim 19, wherein said electrolytic aqueous solution further comprises ascorbic acid; phosphoric acid; citric acid; acetic acid; sorbitol; potassium carbonate; propionic acid; sodium propionate; sucrose; lithium carbonate; lithium citrate; magnesium chloride; sodium teraborate; sodium acetate; sodium sulfate, or a combination thereof. 